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On two quantum approaches to adaptive mutations in bacteria

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 نشر من قبل Vasily Ogryzko V
 تاريخ النشر 2009
  مجال البحث علم الأحياء
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 تأليف Vasily Ogryzko




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I compare two quantum-theoretical approaches to the phenomenon of adaptive mutations, termed here Q-cell and Q-genome. I use fluctuation trapping model as a general framework. I introduce notions of R-error and D-error and argue that the fluctuation trapping model has to employ a correlation between the R- and D- errors. Further, I compare how the two approaches can justify the R-D-error correlation, focusing on the advantages of the Q-cell approach. The positive role of environmentally induced decoherence (EID) on both steps of the adaptation process is emphasized. A starving bacterial cell is proposed to be in an einselected state. The intracellular dynamics in this state has a unitary character and I propose to interpret it as exponential growth in imaginary time, analogously to the commonly considered diffusion interpretation of the Schroedinger equation. Addition of a substrate leads to Wick rotation and a switch from imaginary time reproduction to a real time reproduction regime. Due to the variations at the genomic level (such as base tautomery), the starving cell has to be represented as a superposition of different components, all reproducing in imaginary time. Adidtion of a selective substrate, allowing only one of these components to amplify, will cause Wick rotation and amplification of this component, thus justifying the occurence of the R-D-error correlation. Further ramifications of the proposed ideas for evolutionary theory are discussed.



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